The following relates generally to wireless communication and more specifically to latency reduction techniques in wireless communications.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems, (e.g., a Long Term Evolution (LTE) system). A wireless multiple-access communications system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).
In some instances, transmission errors between mobile devices and base stations are avoided and/or corrected by utilizing an automatic repeat request (ARQ) scheme. An ARQ scheme may be employed to detect whether a received packet is in error. For example, in an ARQ scheme, a receiver may notify a transmitter with a positive acknowledgment (ACK), when a packet is received free from errors; and the receiver may notify the transmitter with a negative acknowledgment (NACK), if an error is detected. A hybrid ARQ (HARQ) scheme may be used to correct some errors and to detect and discard certain uncorrectable packets. In some scenarios, however, the overall HARQ delay may cause certain inefficiencies in wireless communications.
Furthermore, in some cases uplink resources may be allocated to a UE in downlink control information that is transmitted in a downlink transmission from a base station to the UE. The UE may receive the downlink control information, decode the allocated uplink resources, and begin transmitting the associated uplink transmission following a certain time period from a transmission containing the downlink control information. The delay from the reception of the downlink allocation to a start of uplink transmissions may also cause certain inefficiencies in wireless communications.